SoundCraft MPM 12/2, Руководство пользователя

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Repeat this procedure on other channels as required. As more channels
are added to the mix, the meters may move into the red section. Adjust the
overall level using the Master Faders if necessary.
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Listen carefully for the characteristic sound of “feedback”. If you cannot
achieve satisfactory input level setting without feedback, check microphone
and speaker placement and repeat the exercise. If feedback persists, it
may be necessary to use a Graphic Equaliser to reduce the system re-
sponse at particular resonant frequencies.
Note:
The initial settings should only be regarded as a starting point for your mix. It is
important to remember that many factors affect the sound during a live perform-
ance, for instance the size of the audience!
You are now ready to start building the mix and this should be done progressively,
listening carefully for each component in the mix and watching the meters for any
hint of overload. If this occurs, back off the appropriate Channel Fader slightly
until the level is out of the red segments, or adjust the Master Faders.
Remember that the mixer is a mixer, not an amplifier. Increasing the overall level
is the job of the amplifier, and if it is impossible to provide adequate level, it is
probable that the amplifier is too small for the application. Choose your amplifier
carefully, and do not try to compensate for lack of power by using the mixer to
increase output level.
Note:
The level of any source signal in the final output is affected by many factors,
principally the Input Gain control, Channel Fader and Mix Faders. You should try to
use only as much microphone gain as required to achieve a good balance be-
tween signals, with the faders set as described above.
If the input gain is set too high, the channel fader will need to be pulled down too
far in compensation to leave enough travel for successful mixing and there is a
greater risk of feedback because small fader movements will have a very signifi-
cant effect on output level. Also there will be a chance of distortion as the signal
overloads the channel and causes clipping.
If the gain is set too low, you will not find enough gain on the faders to bring the
signal up to an adequate level, and backgound hiss will be more noticeable.
This is illustrated below: